A series of investigations will be undertaken in order to ascertain what relationships exist between phospholipase A2 activity, PG synthetase activity, and PG dehydrogenase and Delta I3-reductase activity, PGs in the epididymal fluids, spermatozoal adenyl cyclase activity, spermatozoal cAMP levels and maturation of the spermatozoa as these cells pass through the epididymis and into the vas deferens. The caput, corpus and cauda epididymides and vas deferens will be cannulated and the fluid containing the spermatozoa will be collected and assayed for pH, PG content, and inhibitors and/or activators of PG synthetase activity (for both spermatozoa and seminal vesicles). Spermatozoa will be assayed for PG synthetase activity, PGE2 and PGF2a content, cAMP content PG dehydrogenase and Delta I3-reductase activity, and adenyl cyclase activity. Exogenous PGE2 will be added to the above spermatozoal fractions in vitro to ascertain if this PG can activate this enzyme. Inhibitors of phospholipase A2 activity and PG synthetase activity will be administered locally to ascertain if they will effectively lower PG and cAMP content of the spermatozoa and thereby prevent normal maturation of these cells as they pass through the epididymis and render the animal temporarily infertile.